Method and composition for adhering to tooth structure

ABSTRACT

A dental adhesive composition has an adhesive component and an activator component. The adhesive composition has a volatile organic solvent component, one or more polymerizable (meth)acrylate compounds optionally containing fillers, and a polymerization photoinitiator. The adhesive component may also be a substantially homogeneous mixture of one or more polymerizable (meth)acrylate compounds and an effective amount of a photoinitiator, without a solvent. The activator component includes an aromatic sulfinate salt and an activator component solvent. A method for adhering a restorative to a dental surface includes preparing the surface for restoration; applying a mixture of an adhesive component and an activator component to the prepared cavity, thereby forming a coated cavity surface; and, applying a direct or indirect dental restorative to the coated cavity surface.

RELATED APPLICATION

This application is a continuation-in-part of pending U.S. Ser. No.09/107,913.

TECHNICAL FIELD

The invention relates to adhesion of dental restoratives to teeth,porcelain, metals, amalgams and other dental surfaces. The inventionprovides a method and composition for adhering to such dental surfaces.Specifically, the inventive compositions include a (meth)acrylateadhesive component optionally containing one or more fillers, and asulfinate salt activator component. The method according to theinvention includes preparing the dental surface, applying the inventivematerial and then applying a dental restorative according to appropriatedirect or indirect dental restoration procedures.

BACKGROUND OF THE INVENTION

It is most desirable, when filling a tooth cavity with a fillingmaterial, such as a polymerizable dental restorative, to ensure goodadhesion between the tooth surrounding the cavity and the set(polymerized) filling material since there is thereby obtained a goodseal between the set filling material and the tooth which prevents, orat least markedly inhibits, ingress of mouth fluids and bacteria intothe filled cavity and thus prevents further decay or loss of the fillingmaterial. In order to achieve good adhesion between the filling materialand the tooth tissues, enamel or dentin, it has been recommended toprovide a primer or adhesive bonding layer intermediate to the fillingmaterial and surfaces of a prepared tooth. The filling material isnormally an amalgam or non-amalgam materials for direct or indirectrestorations.

The priming compositions heretofore known in the art, require theseparate steps of applying a priming material to a prepared dentalsurface, followed by the application of a dental adhesive. Such a methodis described for example, in U.S. Pat. No. 5,595,487 and in U.S. Pat.No. 5,554,030. In practice, it has been found that such multi-stepprocedures are laborious and time consuming. The dental clinicianrequires time effective procedures. Hence, use of these procedures hasbeen undesirable.

A need exists therefore, for a dental composition which willsimultaneously provide a priming and adhesive material intermediate tothe prepared dental surface and the subsequently applied restorativematerial in both direct and indirect dental procedures. By “direct” itis meant a dental procedure where a tooth is prepared to receive adental restorative composition which is formed and hardened in place. An“indirect” procedure is one wherein a dental construct such as an inlay,onlay, bridge, crown or the like is first prepared and then set into theprepared and adhesive-coated tooth.

OBJECTS OF THE INVENTION

It is an object of the present invention to provide a dentalcomposition.

It is another object of the invention to provide such a compositionwhich will enhance adhesion of a dental restorative material to a dentalsurface.

It is still another object of the invention to provide dentalcomposition as above, which is applied as a mixture or as a singlecomposition.

It is a further object of the invention to provide a method of restoringa tooth structure.

It is an additional object of the invention to provide a method asabove, which does not require separate steps for applying a primingcomponent and an adhesive component.

These and other object of the invention, which will become apparent fromthe disclosure and claims to follow, are carried out by the invention ashereinafter described and claimed.

SUMMARY OF THE INVENTION

A dental adhesive composition according to the invention comprises fromabout 5 to about 80 percent by weight of an adhesive or adhesive/primercomponent optionally containing one or more fillers, and from about 20to about 95 percent by weight of an activator component; the adhesivecomponent comprising at least about 35 percent by weight of a volatileorganic solvent component, at least about 5 percent by weight of one ormore polymerizable (meth)acrylate compounds, and an effective amount ofa polymerization photoinitiator; the polymerizable (meth)acrylatecompound being substantially soluble or homogeneously dispersed in saidvolatile organic solvent component.

The adhesive component can also comprise at least about 5% by weight ofone or more (meth)acrylate compounds and an effective amount of aphotoinitiator. The adhesive is a substantially homogeneous mixture ofthe above compounds but in the absence of said volatile organicsolvent(s).

The activator component comprising from about 0.1 to about 10 percent byweight of an aromatic sulfinate salt and from about 90 to about 99.9percent by weight of an activator component solvent. The activatorcomponent may optionally contain additives that promote self-cure and/orlight cure interactions between the adhesive compositions and therestoratives.

A method according to the invention, for adhering a non-amalgam dentalrestorative to a dental surface, comprises the steps of:

-   -   (a) preparing the dental surface for restoration, including        direct and/or indirect restoration;    -   (b) optionally etching the surface with an acid;    -   (c) applying a mixture of an adhesive component and an activator        component to the prepared surface. thereby forming a coated        dental surface; and,    -   (d) applying a non-amalgam dental restorative to the coated        dental surface. It is an aspect of the invention that step (c)        may include applying the adhesive component and the activator        component sequentially rather than mixing them first.

A method according to the invention for adhering an amalgam dentalrestorative to a dental surface, comprises the steps of:

-   -   (a) preparing the surface for restoration;    -   (b) optionally etching the surface with an acid;    -   (c) applying a mixture of an adhesive component and an activator        component to the prepared surface (or sequentially applying        these two components), thereby forming a coated dental surface;    -   (d) optionally applying a chemically curable dental adhesive to        said coated dental surface, wherein the chemically curable        adhesive includes an oxidizing agent and a reducing agent; and,    -   (e) applying an amalgam dental restorative to the coated dental        surface.

PREFERRED EMBODIMENTS FOR CARRYING OUT THE INVENTION

The dental adhesive composition according to the invention is a mixtureof an adhesive component and an activator component. It is to beunderstood that by “adhesive” it is meant either an adhesive or aprimer/adhesive component. As will be discussed below, the adhesivecomponent may include a solvent (the primer/adhesive) or it may be aresin adhesive which is solvent-free. The term “adhesive” will beunderstood to include all such adhesive systems.

One preferred composition has from about 5 to about 80 percent by weightof the adhesive component and from about 20 to about 95 percent byweight of the activator component. The composition may also containfluoride.

The inventive materials may be provided as a single composition, allcomponents being packaged in one bottle for subsequent use, or as a“mixed” system wherein the adhesive component is packaged separatelyfrom the activator component, the two being mixed at the time of use andbefore being used in the inventive method. Both such packagingapplications are within the scope of the invention.

The adhesive component preferably includes at least about 35 percent byweight of a solvent such as water, a volatile organic solvent, ormixtures thereof, and at least about 5 percent by weight of one or morepolymerizable (meth)acrylate compounds, the remaining components to form100 percent by weight of the adhesive component being initiators orother cure components, polymerizable monomers and oligomers,polymerizable phosphates or other ethylenically unsaturated components,other optional fillers, fluoride release compounds, stabilizers and thelike. An example of a useful fluoride release compound is cetylaminehydrofluoride.

The adhesive component may optionally contain a filler including anyfiller that is useful in dental applications. For example, an inorganicfiller such as silanated inorganic silica may be employed. Anotherexample is a sol-gel inorganic/organic nano-scale composite. Aprepolymerized organic filler may also be employed.

The adhesive component preferably includes an effective amount of aphotopolymerization initiator. The polymerizable (meth)acrylatecompounds should be substantially soluble or substantially homogeneouslydispersed in the selected solvent or solvents, and are polymerizable toform a polymeric material. Certain filler materials may not necessarilybe soluble in the solvent(s) and as such are preferably substantiallyhomogeneously dispersed in the adhesive component.

Examples of useful solvents for the adhesive component include ethanol,methanol, isopropanol, dimethyl ketone, ethylmethyl ketone, water, andthe like, as well as mixtures thereof. The adhesive component accordingto the present invention may also be a solvent-free adhesive resin, asdiscussed above.

Preferred polymerizable methacrylate compounds include for example,those monomers having a solubility in water of less than about 5%, andmore preferably have a solubility in water of less than about 1%. Otheruseful polymerizable (meth)acrylate compounds include multifunctionalpolymerizable compounds having at least three (meth)acrylate moietiesand a phosphate moiety. Still further preferred monomers include surfaceactive monomers having acid functional groups and containing(meth)acrylates. Examples of useful acid functional groups includemaleic acid, phosphonic acid, carboxylic acid, sulfonic acid, andmixtures thereof.

Exemplary monomers include diethylene glycol dimethacrylate; triethyleneglycol dimethacrylate; tetraethyleneglycol dimethacrylate;glycerol-1,2-dimethacrylate; glycerol-1,3-dimethacrylate; the reactionproduct of butanediol diglycidyl ester and methacrylic acid;tetrahydrofurfural methacrylate; methacryloxyethyl maleic ester;methacryloxyethyl succinate; urethane dimethacrylate; Bis-GMA(Bis-phenol A Glycydyl Methacrylate, also known as2,2-bis[4-(2-hydroxy-3-methacyloyloxypropoxy)phenyl]propane);trimethylolpropane tri(meth)acrylate; Ethoxylated bisphenol-Adimethacrylate; bisphenol-A dimethacrylate; and, mixtures thereof.Monomers having a solubility in water higher than 5% are less preferredbut still within the scope of the invention. Monomers having asolubility in water less than about 1% are more preferred. Highly watersoluble monomers such as hydroxyethyl methacrylate and hydroxypropylmethacrylate tend to provide lower adhesion and are less suitable foruse in compositions of the invention.

An example of a useful urethane dimethacrylate is 7,7,9,63,65hexamethyl-4,13,60,69-tetra-oxo-3,14,19,24.29,34,39,44,49,54,59,70-dodecanaoxa-5,12,61,68-tetra-azadoheptacontane-1,72diyldimethacrylae, also known as urethane diemthacrylate resin).

A volatile solvent is removed after application of the adhesive and/orprimer/adhesive to the dentine, enamel, metal or other dental surface.The monomer is preferably less volatile than the solvent.

Examples of useful photoinitiators include those useful in dentalapplications, including camphorquinone, diaryliodium metal complexsalts, chromophore-substituted halomethyl-s-triazines, organo-phosphineoxide (preferably a-cleavage type phosphineoxide), and halomethyloxadiazoles, and others conventional in the art, such as those disclosedin U.S. Pat. Nos. 5,595,487, 4,514,342 and 4,514,343 which areincorporated by reference for such disclosure, as well as mixturesthereof. An effective amount of such an initiator is employed, as willhereinafter be exemplified.

The activator component preferably comprises from about 0.1 to about 10,more preferably about 0.5 to about 5, more preferably still about 0.5 toabout 3, percent by weight of a sulfinate salt and from about 90 toabout 99.9, more preferably from about 95 to about 99.5, even morepreferably about 97 to about 99.5, percent by weight of an activatorcomponent solvent, and optionally a reducing agent such asN,N-bis-(2-hydroxyethyl)-p-toluidine (DHEPT). Examples of usefulactivator component solvents include acetone, ethanol, water, dimethylsulfoxide (DMSO), methylene chloride, chloroform, and the like, as wellas mixtures thereof.

Preferred sulfinate salts are aromatic, having the general structure

wherein R₁—R₅ are individually a hydrogen or an alkyl group having from1 to about 6 carbon atom, preferably hydrogen or a methyl group in thepara-position; M is a cation; and, “n” is an integer being 1 to 4.Preferred examples of M^(n+) are sodium, calcium, ammonium, potassium orlithium. Para-toluene sodium or lithium sulfinate and benzene sodium orlithium sulfinate are preferred salts.

The dental adhesive composition as described hereinabove, is employed ininventive methods for restoring teeth. A method according to theinvention, for adhering an amalgam or non-amalgam dental restorative toa dental surface, includes: (a) preparing the dental surface forrestoration; (b) optionally etching the surface with an acid; (c)applying a mixture of an adhesive component and an activator componentto the prepared surface, thereby forming a coated dental surface; and,(d) applying an amalgam or non-amalgam dental restorative to the coateddental surface. As an alternative, in step (c), the adhesive and theactivator components may be applied sequentially instead of being firstmixed. It will also be appreciated that the order of the method stepsaccording to the invention may be varied as appropriate. The inventivemethods and compositions are useful with direct and indirect dentalprocedures. Further, in step (a), it is understood that “preparing thedental surface for restorations” includes preparing the surface for bothdirect and indirect restorations without limitation.

The step of preparing the dental surface, which may be a cavity or thelike, includes conventional techniques such as removing decayed orotherwise damaged portions by mechanical, abrasive, laser or othermeans. The surface can then be cleaned by washing or other techniques.

To enhance mechanical retention of the restorative material to thedental surfaces, the tooth surface may optionally be etched whereas theindirect restoration surface may be sandblasted and/or silanated and/oracid etched where applicable according to conventional techniques. Anyother conventional preparation technique is also within the scope of theinvention. Etching is well known in the art, and any etching techniqueis also within the scope of the invention. For example, etching may becompleted by applying an acid such as phosphoric acid to the prepareddental surface. The etching acid is normally removed by washing and/ordrying.

The mixture of an adhesive component and an activator component as usedin the inventive method, is selected from those inventive dentalcompositions as discussed hereinabove. It is applied to the surface toprovide a coated dental surface.

If employing a non-amalgam type restorative material, such as Prisma TPHSpectrum composite or EnFOrce WF Composite Resin Luting Cement, bothavailable from Dentsply International Inc. (L.D. Caulk Division), therestorative may be applied to the coated dental surface. If therestorative is an amalgam material, such as Dispersalloy (admixed alloy)or Megalloy (spherical alloy) both available from Dentsply InternationalInc. (L.D. Caulk Division), it is sometimes optionally useful to firstapply a chemically curable adhesive to the coated dental surfacefollowed by application of the amalgam restorative. Preferred chemicallycurable adhesives include for example, Amalgam Bonding Base and Catalystavailable from Dentsply International Inc. (L.D. Caulk Division). Suchchemically curable adhesives contain an oxidizing agent such as benzoylperoxide, and a reducing agent such asN,N-bis-(2-hydroxyethyl)-p-toluidine (DHEPT). It will be appreciatedthat this step of applying a chemically curable adhesive when using anamalgam restorative is preferred but is optional.

General Experimental

In order to exemplify the inventive compositions, a dental compositionas above was prepared. The activator component was a substantiallyhomogeneous mixture of 0.6 percent by weight of para-toluene sodiumsulfinate, 79.5 percent by weight of dimethyl ketone and 19.9 percent byweight of ethanol, to form 100 percent by weight of the activatorcomponent. The adhesive component was Prime & Bond® 2.1 (abbreviated P&Bbelow) from Dentsply International Inc., known to contain about 50-80percent by weight of solvent, about 5-15 percent by weight ofmultifunctional polymerizable compounds having at least three(meth)acrylate moieties and a phosphate moiety, and the balance beingother (meth)acrylate monomers and oligomers, one or more fluoriderelease compounds, and other additives. The activator and adhesivecomponents were used in approximately a 1:1 mixture by volume, and thismixture is discussed below as the “inventive composition”.

EXAMPLE 1

This inventive composition was tested for shear bond strength (SBS)using a Single Plane Shear Test Assembly apparatus (SPSTA) as describedby L. G. Watanabe, et al., in Journal of Dental Research, 76 (SpecialEdition) Abs. 1398, 1977 and/or other standard compressive shear bondstrength test methods as described in U.S. Pat. No. 5,645,429 which ishereby incorporated by reference for such disclosure, and for example,in Dental Materials, vol. 3;185, 1987 by Hammesfahr et al. Thecompositions tested included self curing (SC) and light curing (LC orVLC for “visible light cure”) materials. Further, the inventivematerials were tested with etching or non-etching to dental surfaces aswill be noted below, and were also compared to various commerciallyavailable adhesive products. As will be shown in the following tables,the inventive material shows comparable or improved results over thecommercially available products. “SD” as used below is standarddeviation, and “Del.” is dentin or enamel delamination. Cohesive failureas reported indicate bond fracture occurred within either toothsubstrate dentin or enamel or restoratives and are reported as thenumber of failures (F) per the total number tested (T) (F/T). Bothimmediate (15 minute) and 24-hour bond strength of different compositeresin luting cements to human dentin using the inventive composition orother commercially available dual-cure adhesive systems were evaluatedby SPSTA test methods as described above. The results are summarized inTABLE I. TABLE I System Comparison* of The Inventive CompositionImmediate (15 minute) and 24 Hours Shear Bond Strength** Dual-CureUniversal Immediate SBS (MPa) 24 Hrs SBS (MPa) Dental Adhesive X ± SD, X± SD, Systems Dentin Del (%) Dentin Del (%) Comments Dual-Cure Prime &6.72 ± 2.38 20% 10.32 ± 1.75   40% total SC Bond ™ 2.1 (total SC) ≧13.97± 0.96  100% Enforce LC 1′ (Dentsply/Caulk) 8.53 ± 1.98  0% 15.47 ±2.27   75% Primers LC 10″ (total SC) ≧13.67 ± 2.64  100% LC both Primersand Enforce SBMP+ 4.98 ± 1.00 20% 6.36 ± 2.71  20% total SC (per DFU)(3M) 8.98 ± 3.05  0% LC 10″ Activator/Primer All-Bond 2 9.15 ± 0.73 60%11.89 ± 2.91   80% Primers LC 20″ (BISCO, Inc.) (per DFU) OptiBond 8.22± 3.70  0% 7.68 ± 1.72  0% Nexus Cement LC 1′ (Ker) (per DFU)*All the test samples for different system were prepared according tothe manufacturer's directions for use (DFU), and the manufacturer'srecommended resin cement was used for different system, i.e. theinventive composition/EnForce WF (Caulk), SBMP+/3M Resin Cement (3M),All-Bond 2/Duo-Link (BISCO, Inc.), and OptiBond/Nexus (Kerr).**SBS was tested using Single Plane Shear Test Assembly.

As indicated by the SBS data, the inventive composition, two-bottledual-cure dental adhesive system showed equivalent (or improved) bondingperformance to competitors' multi-bottle dental adhesive system (3M'sSBMP+, Bisco's All-Bond and Kerr's OptiBond), with the additionaladvantages of simplicity, i.e. simple technique, less total applicationtime, time/cost saving, fluoride-release, thin-film thickness, and thelike.

EXAMPLE II

Using the SPSTA test method, bond strength of different restorativematerials to human teeth (dentin) using the inventive composition wasevaluated and the results are shown in TABLE II. TABLE II 24 hr. ShearBond Strength of Different Restoratives to Human Teeth Using TheInventive Composition BONDING SURFACE Inventive 24 Hour SUBSTRATETREATMENT Composition RESTORATIVES Shear Bond Strength (MPa) DentinEtched Self Cure (SC) SC Enforce ™ WF 11.20 ± 2.58 80% Dentin EtchedVisible Light SC Enforce ™ WF 13.93 ± 1.81 75% Cure (VLC) Dentin EtchedVisible Light SC Enforce ™ WF 15.47 ± 2.27 75% Cure (VLC) Dentin EtchedVisible Light VLC Enforce ™ WF ≧13.67 ± 2.64  100%  Cure (VLC) DentinUnetched Self Cure (SC) SC Enforce ™ WF  4.18 ± 2.91  0% Dentin UnetchedVisible Light SC Enforce ™ WF 9.79 ± 3.0 60% Cure (VLC) Dentin EtchedSelf Cure (SC) SC FluoroCore ™ 8.90 ± 3.0 33% Dentin Etched VisibleLight VLC TPH ™ 31.34 ± 3.82 10% Cure (VLC) Spectrum Composite

As can be seen from the SBS results in TABLE II (and TABLE III below)the inventive composition can be used to adhere different restorativematerials to tooth structure in a variety of direct and indirectrestoration applications with good bonding performance.

EXAMPLE III

Using the SBS test method as described in Dental Materials, Vol. 3;185,1987, and in the incorporated U.S. Pat. No. 5,645,429, 24-hour enamelSBS of different restoratives used in direct and/or indirectrestorations using the inventive composition was evaluated. The resultsare summarized in TABLE III. TABLE III 24 Hour SBS* of DifferentRestoratives to Human Tooth Using the Inventive Composition BONDINGSURFACE INVENTIVE 24 Hrs. SBS (MPa) SUBSTRATE TREATMENT COMPOSITIONRESTORATIVES X ± SD: Enamel Del (%) Enamel Etched Self Cure (SC)¹ SCEnforce ™ WF¹ 26.8 ± 4.7 100% Enamel Etched Visible Light Cure²(VLC) VLCEnforce ™ WF² 23.7 ± 4.8 100% Enamel Etched Visible Light Cure³(VLC) VLCTPH ™ 31.0 ± 8.0  80% Spectrum Composite³*SBS was tested using Caulk's Compressive Shear Bond Strength TestMethod¹Bonding Protocol-1(total SC): Etched Enamel (Caulk 34% toothgel/15″)/P&B 2.1 & SC Activator (1/1 premix)[1C/wet, NC]/Enforce(SC)²Bonding Protocol-2: Etched Enamel (Caulk 34% tooth gel 15″)/P&B 2.1 &SC Activator (1/1 premix)[1C/wet, LC 10″]/Enforce(LC 40″)³Bonding Protocol-3: Etched Enamel (Caulk 34% tooth gel 15″)/P&B 2.1 &SC Activator (1/1 premix)[1C/wet, LC 10″]/TPH Spectrum (LC40″)

As indicated by the 24 hour enamel SBS data in TABLE III, the inventivecomposition as a 2-bottle dual cure dental adhesive system showed verygood bonding performance (up to 31 MPa, with 100% cohesive failurewithin human enamel) to human enamel (even in total self cure mode) inrelevant to direct and indirect dental applications.

EXAMPLE IV

Using the SBS test method as in Example III, except that a porcelainsubstrate is used in place of human enamel, 24 hour SBS of Enforce ResinCement to an all-ceramic substrate (commercially available from DENTSPLYInternational Inc.) using the inventive composition was tested. Theobtained results are shown in TABLE IV, indicated that the inventivecomposition can be used to adhere to a porcelain substrate with highbond strength. TABLE IV 24 Hour SBS* of Enforce WF (B1) Cement toAll-Ceramic Substrate Using the Inventive Composition Bonding X ± SD;Substrate Bonding Protocol # Coh (MPa) Porcelain Control: substrateporcelain (microetched w/ 12.5 ± 3.9; 50 μm alumina, then silanated perDFU)/ 0/6 Enforce WF [B1](1/1)(LC) Porcelain substrate porcelain(microetched, 14.8 ± 4.1; then silanated per DFU)/P&B 2.1 & 0/7 SCA (1/1mix) [C/NC ]/ Enforce WF [B1](1/1)(SC) Porcelain Substrate porcelain(microetched, 25.0 ± 6.6; (Substrate then silanated per DFU)/P&B 2.1 &SCA 6C/6   porcelain) (1/1 mix) [C/LC]/Enforce WF [B1](1/1)(LC)Porcelain Substrate porcelain (Microetched, 11.1 ± 5.0; (Substrate HFetched/60″, then silanated)/ 4C/5   porcelain) Enforce WF [B1](1/1)(LC)Porcelain Substrate porcelain (Microetched,  20.7 ± 3.51  (Substrate HFetched/60″, silanated)/P&B 2.1(1/1 mix) 5C.5 porcelain) [C/NC]/EnforceWF [B1](1/1)(SC)*SBS was tested using Caulk's Compressive Shear Bond Strength TestMethod.

EXAMPLE V

Using the same test method as in Example IV, the inventive compositionwas evaluated for simulating a clinical “Maryland Bridge” application.The results are shown in TABLE V. These data show the inventivecomposition can also be used to strongly bond non-precious metals(rexillium III) to human enamel in relevant clinical applications. TABLEV 24 hr. SBS of Non-Precious Metal (Rexillium III) to Etched HumanEnamel Using the Inventive Composition and Enforce WF (Opaque)* BondingSubstrate Bonding Protocol X ± SD (MPa) Fracture Mode Enamel Enamel (34%Gel/30″)/Prime & 23.2 ± 15.4 33% enamel coh. Fail, Bond 2.1 & SCActivator(1C/wet,NC)/ (SC mode) others adh/coh mixed. Enforce w/F[OP](1/1) (1L, SC 6′, LC 3 × 20″)/ Rex III[microetched, Prime & Bond 2.1& SC Activator (1C/wet, LC 10″)] Enamel Enamel (34% Gel/30″)/Prime &13.1 ± 9.4  Mixed failure Bond 2.1 & SC Activator(1C/wet, (Add LC)(Cement) Coh/adh. LC 10″)/Enforce w/F [OP](1/1) (1L, SC 6′, LC 3 × 20″)/Rex III[microetched, Prime & Bond 2.1 & SC Activator (1C/wet, LC 10″)]*SBS was tested by Caulk's Compressive Shear Bond Strength Test Methodwhere 3.15 mm Rexillium III Post used

EXAMPLE VI

Using the SPSTA test method the inventive composition was evaluated forits adhesive amalgam bonding application in comparison with severalcommercially available adhesive systems. The obtained amalgam bondstrength to dentin data is summarized in TABLE IV. As indicated by thesedata, the inventive composition showed acceptable adhesive bondingperformance. TABLE VI 24 Hour Shear Bond Strengh* of Fresh Amalgam withHuman Dentin Sample Bonding Protocol X(SD), #Del. Prime & Bond ® 2.1Etched dentin(Caulk gel/15″)/P&B 2.1&SC 4.1 (1.3), 0/5 Dual CureAdhesive Activator (1/1 premix)[1C/wet, NC]/Caulk SC Bonding AgentBase/catalyst (1/1 equal drop mix) [1L, SC]/Dispersalloy ® amalgam SBMP+Etched dentin(3M etchang/15″)/Activator/Primer 2.2 (0.9), 0/5 [1C,NC]/Adhesive & Catalyst (1/1mix) [1 Thin Layer, SC]/Dispersalloy ®amalgam Per DFU SBMP+ Repeat amalgam bonding, per DFU 3.7 (0.2), 0/5OptiBond ® Per DFU: Etched (Kerr's etching/15″)/ 1.8 (1.9), 0/5 Primer1[C/scrub 30″, NC]/Adhesive 2[1 thin Layer; LC 30″]/Dispersalloy ®amalgam All-Bond ® 2 Per DFU: Etched dentin(Uni-Etch/15″)/ 2.6 (1.8),0/5 Primer P&B(1/1 mix)[5C, LC20″]/Pre-Bond&D/E Bond (1/1 mix)[1 ThinLayer, SC]/Dispersalloy ® amalgam Amalgam Bond Plus Unetcheddentin/Activator/ahd. Agent/ 6.5 (1.7), 0/5 w/HPA Mix (base/cat/HPA)[1L,SC]/ Dispersalloy ® amalgam Per DFU Amalgam Bond Plus Unetcheddentin/Activator/adh.agent/ 2.4 (1.8), 0/5 w/o HPA Mix (base&cat)[1L,SC]/ →1.7 (0.6), 0/5 Dispersalloy ® amalgam

(repeated BS)*SBS was tested using Single Plane Shear Test Assembly

It is apparent therefore, that the dental compositions as describedherein are effective in carrying out the objects of the invention. Whilethe principles of the invention have been made clear by the illustrativeembodiments discussed, those skilled in the art will appreciate thatmodifications to composition components including the addition of othercomponents to the composition for promoting chemical or photocurepolymerization, amounts, grades, process and method conditions and thelike, can be made and still fall within the scope of the thoseprinciples and of the invention.

1. A dental adhesive composition comprising from about 5 to about 80percent by weight of an adhesive component and from about 20 to about 95percent by weight of an activator component; said adhesive componentcomprising at least about 35 percent by weight of a solvent component,at least about 5 percent by weight of one or more polymerizable(meth)acrylate compounds, an effective amount of a polymerizationinitiator and optionally a filler component.
 2. A composition as inclaim 1, wherein said polymerizable (meth)acrylate compound issubstantially soluble in said solvent component.
 3. A composition as inclaim 1, wherein said solvent component is selected from the groupconsisting of ethanol, methanol, isopropanol, dimethyl ketone,ethylmethyl ketone, water, and mixtures thereof.
 4. A composition as inclaim 1, wherein said more polymerizable (meth)acrylate compounds areselected from the group consisting of monomers having a solubility inwater of less than about 5%.
 5. A composition as in claim 1, whereinsaid more polymerizable (meth)acrylate compounds are selected from thegroup consisting of multifunctional polymerizable compounds having atleast three (meth)acrylate moieties and a phosphate moiety.
 6. Acomposition as in claim 1, wherein said more polymerizable(meth)acrylate compounds are selected from the group consisting ofsurface active monomers having acid functional groups and containing(meth)acrylates.
 7. A composition as in claim 6, wherein said acidfunctional group is selected from the group consisting of maleic acid,phosphonic acid, carboxylic acid, sulfonic acid, and mixtures thereof.8. A composition as in claim 1, wherein said more polymerizable(meth)acrylate compounds are selected from the group consisting ofdiethylene glycol dimethacrylate; triethylene glycol dimethacrylate;tetraethyleneglycol dimethacrylate; glycerol-1,2-dimethacrylate;glycerol-1,3-dimethacrylate; the reaction product of butanedioldiglycidyl ester and methacrylic acid; tetrahydrofurfural methacrylate;methacryloxyethyl maleic ester; methacryloxyethyl succinate; urethanedimethacrylate; Bis-GMA; trimethylolpropane tri(meth)acrylate;ethoxylated bisphenol-A dimethacrylate; bisphenol-A dimethacrylate; and,mixtures thereof.
 9. A composition as in claim 1, wherein saidpolymerizable (meth)acrylate compound is urethane diemthacrylate resin.10. A composition as in claim 1, wherein said filler is selected fromthe group consisting of silanated inorganic silica; a sol-gelinorganic/organic nano-scale composite; and, a prepolymerized organicfiller.
 11. A composition as in claim 1, further comprising a fluoriderelease agent.
 12. A composition as in claim 1, further comprising acure additive selected from the group consisting of self-cure and lightcure additives and mixtures thereof, such that said additive promotescure interactions between the composition and a restorative material.13. A composition as in claim 1, wherein said activator componentcomprises from about 0.1 to about 10 percent by weight of an aromaticsulfinate salt and from about 90 to about 99.9 percent by weight of anactivator component solvent.
 14. A composition as in claim 13, whereinsaid activator component solvents is selected from the group consistingof acetone, ethanol, water, dimethyl sulfoxide (DMSO), methylenechloride, chloroform, and mixtures thereof.
 15. A composition as inclaim 13, wherein said aromatic sulfinate salt has the structure

wherein R₁—R₅ are individually a hydrogen or an alkyl group having from1 to about 6 carbon atom; M is a cation; and, “n” is an integer of from1 to
 4. 16. A composition as in claim 15, wherein said aromaticsulfinate salt has a hydrogen or a methyl group in the para-position.17. A composition as in claim 15, wherein M is selected from the groupconsisting of sodium, calcium, potassium, ammonium and lithium.
 18. Acomposition as in claim 15, wherein said aromatic sulfinate salt ispara-toluene sodium sulfinate, para-toluene lithium sulfinate, benzenesodium sulfinate, benzene lithium sulfinate or mixtures thereof.
 19. Acomposition as in claim 1, wherein said initiator is a photoinitiator.20. A composition as in claim 19, wherein said photoinitiator isselected from the group consisting of camphorquinone, diaryliodium metalcomplex salts, chromophore-substituted halomethyl-s-triazines, phosphineoxide, halomethyl oxadiazoles, and mixtures thereof.
 21. A dentaladhesive composition comprising a substantially homogeneous mixture ofone or more polymerizable (meth)acrylate compounds and an effectiveamount of a photoinitiator and optionally one or more fillers.
 22. Amethod according to the invention, for adhering a non-amalgam dentalrestorative to a dental surface, comprises the steps of: (a) preparingthe dental surface for restoration; (b) optionally etching the surfacewith an acid; (c) applying an adhesive component and an activatorcomponent to the prepared surface, thereby forming a coated dentalsurface; and, (d) applying a non-amalgam dental restorative to thecoated dental surface.
 23. A method as in claim 22, wherein said mixturecomprises from about 5 to about 80 percent by weight of an adhesivecomponent and from about 20 to about 95 percent by weight of anactivator component; said adhesive component comprising at least about35 percent by weight of a solvent component, at least about 5 percent byweight of one or more polymerizable (meth)acrylate compounds, aneffective amount of a polymerization initiator, and optionally a fillercomponent.
 24. A method as in claim 22, wherein said mixture asubstantially homogeneous mixture of one or more polymerizable(meth)acrylate compounds and an effective amount of a photoinitiator andoptionally one or more fillers.
 25. A method as in claim 22, whereinsaid polymerizable (meth)acrylate compound is substantially soluble orsubstantially homogeneously dispersed in said solvent component.
 26. Amethod as in claim 22, wherein said solvent component is selected fromthe group consisting of ethanol, methanol, isopropanol, dimethyl ketone,ethylmethyl ketone, water, and mixtures thereof.
 27. A method as inclaim 22, wherein said more polymerizable (meth)acrylate compounds areselected from the group consisting of monomers having a solubility inwater of less than about 5%.
 28. A method as in claim 22, wherein saidmore polymerizable (meth)acrylate compounds are selected from the groupconsisting of multifunctional polymerizable compounds having at leastthree (meth)acrylate moieties and a phosphate moiety.
 29. A method as inclaim 22, wherein said more polymerizable (meth)acrylate compounds areselected from the group consisting of surface active monomers havingacid functional groups and containing (meth)acrylates.
 30. A method asin claim 22, wherein said more polymerizable (meth)acrylate compoundsare selected from the group consisting of diethylene glycoldimethacrylate; triethylene glycol dimethacrylate; tetraethyleneglycoldimethacrylate; glycerol-1,2-dimethacrylate;glycerol-1,3-dimethacrylate; the reaction product of butanedioldiglycidyl ester and methacrylic acid; tetrahydrofurfural methacrylate;methacryloxyethyl maleic ester; methacryloxyethyl succinate; urethanedimethacrylate; Bis-GMA; trimethylolpropane tri(meth)acrylate;ethoxylated bisphenol-A dimethacrylate; bisphenol-A dimethacrylate; and,mixtures thereof.
 31. A method as in claim 22, wherein said activatorcomponent comprises from about 0.1 to about 10 percent by weight of anaromatic sulfinate salt and from about 90 to about 99.9 percent byweight of an activator component solvent.
 32. A method as in claim 31,wherein said activator component solvent is selected from the groupconsisting of acetone, ethanol, water, dimethyl sulfoxide (DMSO),methylene chloride, chloroform, and mixtures thereof.
 33. A method as inclaim 31, wherein said aromatic sulfinate salt has the structure

wherein R₁—R₅ are individually a hydrogen or an alkyl group having from1 to about 6 carbon atom; M is a cation; and, “n” is an integer of from1 to
 4. 34. A method as in claim 33, wherein said aromatic sulfinatesalt has a hydrogen or a methyl group in the para-position.
 35. A methodas in claim 33, wherein M is selected from the group consisting ofsodium, calcium, ammonium, potassium and lithium.
 36. A method as inclaim 33, wherein said aromatic sulfinate salt is para-toluene sodiumsulfinate, para-toluene lithium sulfinate, benzene sodium sulfinate,benzene lithium sulfinate or mixtures thereof.
 37. A method as in claim22, wherein said initiator is a photoinitiator.
 38. A method as in claim37, wherein said photoinitiator is selected from the group consisting ofcamphorquinone, diaryliodium metal complex salts,chromophore-substituted halomethyl-s-triazines, α-carbonylphophineoxide, halomethyl oxadiazoles, and mixtures thereof.
 39. Amethod as in claim 22, wherein said step (c) includes applying a mixtureof said adhesive component and said activator component.
 40. A method asin claim 22, wherein said step (c) includes sequentially applying saidadhesive component and then applying said activator component.
 41. Amethod according to the invention for adhering an amalgam dentalrestorative to a dental surface, comprises the steps of: (a) preparingthe surface for restoration; (b) optionally etching the surface with anacid; (c) applying a mixture of an adhesive component and an activatorcomponent to the prepared surface, thereby forming a coated dentalsurface; (d) optionally applying a chemically curable dental adhesive tosaid coated dental surface, wherein the chemically curable adhesiveincludes an oxidizing agent and a reducing agent; and, (e) applying anamalgam dental restorative to the coated dental surface.